Method of severing metal articles



Sept. 11, 1962 J. C. WALTERS ETAL METHOD OF SEVERING METAL ARTICLES FIG. 5

Filed Sept. 5, 1957 INVENTORS JOHN C. WALTERS IVAR S. LAWSON BY amma Wm ATTORNEY United States Patent 3,052,975 METHOD OF SEVERING METAL ARTICLES John C. Walters, P.O. Box 74, Lakewood, N.Y., and Ivar S. Lawson, RED. 2, Ashville, N.Y. Filed Sept. 5, 1957, Ser. No. 682,129 1 Claim. (Cl. 29413) This invention relates to the art of making tubing and like members in sections of predetermined length from a continuous flat ribbon of material and is particularly directed to the method of severing such members by initially partially severing the material by scoring the same to weaken the material along a narrow transverse line, forming the member into a predetermined cross section and subsequently finally severing the member at the weakened line by inducing stress to the completed member into the area of the weakened lines.

More broadly stated, the invention is directed to the method of severing tubing and like members into sections at predetermined intervals previously weakened by transverse score lines and subsequently oscillating the member in the area of the score lines to induce sufficient stress to rupture the member into sections medially of the score line.

Further objects and advantages of the invention will become apparent from a study of the following description when taken in connection with the accompanying drawing in which:

FIG. 1 is a fragmentary schematic view in side elevation, partly in section, of the scoring and initial forming steps of the present invention.

FIG. 2 is a fragmentary schematic view in top plan of the final forming and severing steps.

FIG. 3 is a detail view in the direction of the arrows 33 of FIG. 2.

FIG. 4 is a view similar to FIG. but illustrating a modified arrangement.

FIG. 5 is a sectional detail view taken on a line 5-5 of FIG. 3.

FIG. 6 is a sectional detail view of a section of the tubing at the score line.

Referring to the drawing wherein the showings are for the purposes of illustration only, and not for the purposes of limiting the invention, FIG. 1 diagrammatically illustrates the initial steps of scoring and partly forming a continuous strip of sheet metal which may be supplied from a coil of stock 12, supported by a suitable rack 10. The strip or ribbon 14 of stock emerges from the coil in a generally horizontal plane and passes through a scoring station which is inclusive of a table 16 and a vertically moveable scoring die 18, arranged to produce a transverse score from edge to edge of the strip. The scoring may be provided by any suitable means preferably at measured intervals in the strip stock. By way of example, the measuring and scoring may be performed in accordance with Lawson Patent No. 2,781,816 of February 19, 1957. For most purposes, the ribbon is scored on the top surface of the strip where it will be noted that the score line 19 is of generally V shape, and then passes into a plurality of roll forming stages indicated generally at 20 and comprising a plurality of pairs of forming rolls 21, 22 and 23, 24 for partially initially forming the scored strip into suitable cross section. For purposes of illustration, the finished formed section is generally tubular, although it could be of channel or other form.

Referring now to FIG. 2 of the drawing wherein the final forming stage is illustrated as including upper forming roll 25 and final severing stage, the formed member 27 emerges from the roll forming dies and preferably passes through a pair of guide rolls 29 and 30, and through a guide member 32, which is preferably provided with a bore or aperture 33 conforming in contour with that of the formed member. From the guide 32 the formed member passes into an eccentric rotary head indicated generally at 34, driven from a suitable variable speed electric motor 35, from which head the formed member passes through a second guide 37, generally similar to the guide 32. As shown in FIGS. 3 and 5, the rotary head 34 has been illustrated as generally including a tubular shaft 38 anti-frictionally mounted on spaced roller bearings 39 and 40, the shaft 38 being provided at one end with an enlarged head portion 42 having an eccentric bore 44 within which is pressed roller bearing 45 having an inner race 46 provided with a central aperture 48 for slidably receiving the advancing formed member 27. It will be understood that other than tubular sections could require an aperture other than of symmetrical shape.

The eccentric rotary head is preferably of auto-centering type and may be provided with means to vary its speed and throw. The purpose of the rotary head is to induce stress to the formed member in the area of the score 19 and between guides 32 and 37, rotation of the head being furnished from the motor 35 through V pulley 50, belt 51, and V pulley 52. As above noted, the motor 35 is of the variable speed type and thus can be controlled to rotate the head 34 at any suitable speed.

Rotation of the head 34 with the formed stock therein at predetermined speed serves to deflect the formed member to just under the elastic limit of the weakened or scored section. It is intended that the stress intensity be maintained sufiiciently low so as not to impair the usefulness of the material. In other words, the speed of oscillation or gyration, as Well as the degree of throw and the length of material stressed, are all factors that can be varied according to the material and its section. By maintaining the stress intensity below the elastic limit of the full section, but at or slightly above the elastic limit of the weakened section, it will be clear that the material will rupture at the weakened section without distorting the adjacent full section. As the stress is induced by oscillating or gyrating a length or section of material, it is clear that the material at the weakened section will be alternately placed under compression and tension at comparatively high frequency which causes the weakened section to fracture or rupture and thus cause separation medially of the score line.

The foregoing arrangement is particularly applicable to comparatively long lengths of formed material. In the event that short lengths of material are to be severed, the arrangement shown in FIG. 4 can be utilized. It will be noted that guide 37 has been replaced by a tubular member of larger inside diameter than provided in the guide 37, which permits the leading end of the formed member to gyrate or oscillate freely, but within predetermined limits. The inside diameter of this tubular member 55 is preferably calculated to permit the formed member to be deflected thereby an amount sufficient to rapidly reverse the stress induced by the gyrating action of the rotary head 34. In this instance, the end of the formed member is also eccentrically deflected to a point below the elastic limit of the full section, but at or above the elastic limit of the weakened section. This results in a rupture of the section at the score line, and as the severed section is short, a suitable means may be provided to guide or direct such sections out of member 55. This is desirable as the process is generally a continuous one in which the leading sections are severed in timed relation to the speed of the forming operation.

What is claimed is:

The method of severing a series of connected members into sections at predetermined intervals previously weakened by transverse score lines consisting of guiding the members for longitudinal movement, and successively eccentrically oscillating adjacent pairs of members around their longitudinal axes between spaced points with the score lines therebetween to thereby flex the members through 360 and induce sufficient stress throughout the score lines to rupture and thereby sever the members into sections at said score lines.

References Cited in the file of this patent UNITED STATES PATENTS 1,309,354 Dallmeyer et a1 July 8, 1919 1,756,448 Bigney Apr. 29, 1930 1,835,002 Birckmayer Dec. 8, 1931 2,187,740 Hothersall Jan. 23, 1940 2,444,463 Nordquist July 6, 1948 2,608,219 McDaniel Aug. 26, 1952 2,766,516 Chantler Oct. 16, 1956 2,862,292 Lawson Dec. 2, 1958 

